Briefly Noted

Genetic Abnormalities in the Pathogenesis of Sweet Syndrome and Pyoderma Gangrenosum

Sweet syndrome and pyoderma gangrenosum are neutrophilic dermatoses, rare disorders whose pathogenesis is poorly understood. Despite apparent associations with inflammatory bowel disease, rheumatoid arthritis, and hematologic malignancies, at least half of cases are idiopathic. Infiltration of skin with polymorphonuclear leukocytes is present in both conditions. A similar disease in mice produces skin with a moth-eaten appearance; it is characterized by neutrophilic infiltration of the skin, peripheral blood, lungs, and spleen. Caused by failure of apoptosis, the disorder has been linked to a genetic defect in the protein tyrosine phosphatases nonreceptor ty…